I thought about it, but those are typically such separate communities that they'll probably want their own sites. If people really think that LispForum should cater toward anything Lisp-like, we can easily extend it to do so. Even if Scheme was included, I'd think that Emacs Lisp would probably be a stretch. If you really want to talk about Emacs Lisp generally, you could do so in the Emacs forum on this site and I wouldn't mind. There's crossover there, so just do it and we'll see what happens.

Personally I think it'd be nice to embrace all of the Lisp variants. Scheme, Emacs Lisp, Clojure, newLISP, Arc, whatever else. Is there any other place where people from all of these communities can get together and mingle and share ideas?